1
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Obey TJN, Nichol GS, Love JB. Controlled and sequential single-electron reduction of the uranyl dication. Dalton Trans 2024; 53:16229-16240. [PMID: 39302243 DOI: 10.1039/d4dt02367f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2024]
Abstract
A flexible tripodal pyrrole-imine ligand (H3L) has been used to facilitate the controlled and sequential single-electron reductions of the uranyl dication from the U(VI) oxidation state to U(V) and further to U(IV), processes that are important to understanding the reduction of uranyl and its environmental remediation. The uranyl(VI) complexes UO2(HL)(sol) (sol = THF, py) were straightforwardly accessed by the transamination reaction of H3L with UO2{N(SiMe3)2}2(THF)2 and adopt 'hangman' structures in which one of the pyrrole-imine arms is pendant. While deprotonation of this arm by LiN(SiMe3)2 causes no change in uranyl oxidation state, single-electron reduction of uranyl(VI) to uranyl(V) occurred on addition of two equivalents of KN(SiMe3)2 to UO2(HL)(sol). The potassium cations of this new [UVO2(K2L)]2 dimer were substituted by transmetalation with the appropriate metal chloride salt, forming the new uranyl(V) tetra-heterometallic complexes, [UVO2Zn(L)(py)2]2 and [UVO2Ln(Cl)(L)(py)2]2 (Ln = Y, Sm, Dy). The dimeric uranyl(V)-yttrium complex underwent further reduction and chloride abstraction to form the tetrametallic U(IV) complex [UIVO2YIII(py)]2, so highlighting the adaptability of this ligand to stabilise a variety of different uranium oxidation states.
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Affiliation(s)
- Tom J N Obey
- EaStCHEM School of Chemistry, Joseph Black Building, University of Edinburgh, Edinburgh EH9 3FJ, UK.
| | - Gary S Nichol
- EaStCHEM School of Chemistry, Joseph Black Building, University of Edinburgh, Edinburgh EH9 3FJ, UK.
| | - Jason B Love
- EaStCHEM School of Chemistry, Joseph Black Building, University of Edinburgh, Edinburgh EH9 3FJ, UK.
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2
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Srivastava A, Ali SM, Dumpala RMR, Kumar S, Kumar P, Rawat N, Mohapatra PK. Unusual redox stability of pentavalent uranium with hetero-bifunctional phosphonocarboxylate: insight into aqueous speciation. Dalton Trans 2024; 53:7321-7339. [PMID: 38591248 DOI: 10.1039/d4dt00173g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
The +5 state is an unusual oxidation state of uranium due to its instability in the aqueous phase. As a result, gaining information about its aqueous speciation is extremely difficult. The present work is an attempt in that direction and it provides insight into the existence of a new pentavalent species in the presence of hetero-bifunctional phosphonocarboxylate (PC) chelators, other than the carbonate ion, in the aqueous medium. The aqueous chemistry of pentavalent uranium species with three environmentally relevant PCs was probed using electrochemical and DFT methods to understand the redox energy and kinetics of conversion of the U(VI)/U(V) couple, stability, structure, stoichiometry, binding modes, etc. Interestingly, pentavalent uranium complexes with PCs are quite persistent over a wide range of pH starting from acidic to alkaline conditions. The PC chelators block the cation-cation interaction (CCI) of U(V) through strong hetero-bidentate chelation and intermolecular hydrogen bonding (IMHB) interactions which stabilize the pentavalent metal ion against disproportionation. For uranyl species in the presence of PCs, acting as chelators, CV plots were obtained at varying pH values from 2 to 8. The obtained results indicate an irreversible single redox peak involving U(VI) to U(V) conversion and association of a coupled chemical reaction with the electron transfer step. ESI-MS studies were performed to understand the speciation effect on the U(VI)/U(V) redox couple with varying pH. Speciation modelling of U(V) with the PC ligands was carried out, which indicated that the U(V) is redox stable in nearly 47% of the pH region in the presence of the PCs as compared to the carboxylate-based chelators. The free energy and reduction potential of the U(V) complexes and the reduction free energy and disproportionation free energy for the U(VI)/U(V) couple were determined by DFT computations in the presence of the PCs. In situ spectroelectrochemical spectra were recorded to provide evidence for the existence of U(V) species with PCs in the aqueous medium and to acquire its absorption spectra. The present study is highly significant for understanding the coordination chemistry of pentavalent uranium species, accurate modelling of uranium, and isolation of U(V).
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Affiliation(s)
- Ashutosh Srivastava
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai, India-400085.
| | - Sk Musharaf Ali
- Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai, India-400085
| | | | - Sumit Kumar
- Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai, India-400085
| | - Pranaw Kumar
- Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai, India-400085
| | - Neetika Rawat
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai, India-400085.
| | - P K Mohapatra
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai, India-400085.
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3
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Kersten B, Akolkar R, Duval CE. An electrochemical technique for sensing uranium adsorption and desorption. Anal Chim Acta 2023; 1284:342003. [PMID: 37996162 DOI: 10.1016/j.aca.2023.342003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 10/27/2023] [Accepted: 11/03/2023] [Indexed: 11/25/2023]
Abstract
Uranium is a toxic, heavy metal that can pose elevated health risks if leached into the environment. Uranium mobility is dependent on many factors, including speciation, solution pH, ligands in solution, and presence of surfaces. Surface adsorption is one phenomenon that inhibits uranium mobility in the environment and is studied as a naturally occurring phenomenon as well an intentional tool for environmental remediation. This work presents and validates a potentiometric, electrochemical technique for sensing uranium adsorption on and desorption from an electrochemically active surface solely through changes of the electrode potential. This novel electrochemical technique presents a new lens to study adsorption that complements external techniques (e.g., spectroscopy). Indication of adsorption and desorption via the electrochemical technique are gravimetrically validated using an electrochemical quartz crystal microbalance. This work contributes a unique, complementary technique that corroborates the adsorption of uranium on an electrode surface.
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Affiliation(s)
- Bethany Kersten
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, 44106, Cleveland, OH, USA
| | - Rohan Akolkar
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, 44106, Cleveland, OH, USA
| | - Christine E Duval
- Department of Chemical and Biomolecular Engineering, Case Western Reserve University, 10900 Euclid Ave, 44106, Cleveland, OH, USA.
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4
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Bessonov AA, Shilov VP. Behavior of Plutonium(V) in the Environment. RADIOCHEMISTRY 2022. [DOI: 10.1134/s1066362222060029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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5
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Shilov VP, Fedoseev AM, Myasoedov BF. Disproportionation of Actinides in Aqueous and Organic Media. RADIOCHEMISTRY 2022. [DOI: 10.1134/s1066362222030092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Verma PK, Mohapatra PK. Fate of Neptunium in nuclear fuel cycle streams: state-of-the art on separation strategies. RADIOCHIM ACTA 2022. [DOI: 10.1515/ract-2022-0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Neptunium, with a half life of 2.14 million years is one of the most notorious activation products in the nuclear fuel cycle. It has been more than 5 decades in the reprocessing of nuclear fuels by the well documented PUREX process, but the fate of Np in the PUREX cycle is still not well controlled. Although Np being stable in its pentavalent state in low acid media, its starts to undergo disproportionation at higher acidities. This disproportionation along with the oxidizing conditions of the HNO3 medium makes Np to exits as Np(IV), Np(V) and Np(VI) in the dissolver solution. The overall extractability of Np in the co-decontamination step of the PUREX cycle is dependent on its oxidation state in the medium as Np(VI) and Np(IV) being extractable while Np(V) being least extractable. The present review article discusses about the speciation of Np in HNO3 and its disproportionation. The variety of redox reagents are discussed for their effectiveness towards controlling Np redox behavior in the HNO3 media. The extraction of Np with the different class of extractant has also been discussed and the results are compared for better understanding. Solid phase extraction of Np using both commercially available resin and lab based synthesized resins were discussed. The anion exchange resins with the different cationic centers were shown to behave differently towards the uptake of Np form the acidic medium. The present review also highlight the chemical conditions required for controlling or minimizing the fate of Np in different process streams of the nuclear fuel cycle.
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Affiliation(s)
- Parveen K. Verma
- Radiochemistry Division , Bhabha Atomic Research Centre , Trombay , Mumbai 400085 , India
| | - Prasanta K. Mohapatra
- Radiochemistry Division , Bhabha Atomic Research Centre , Trombay , Mumbai 400085 , India
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7
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Pyrch M, Augustine L, Williams J, Mason SE, Forbes T. Use of vibrational spectroscopy to identify the formation of neptunyl-neptunyl interactions: A paired Density Functional Theory and Raman spectroscopy study. Dalton Trans 2022; 51:4772-4785. [DOI: 10.1039/d2dt00200k] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract: Actinyl-Actinyl interactions (AAIs) occur in pentavalent actinide systems, particularly for Np(V), and lead to complex vibrational signals that are challenging to analyze and interpret. Previous studies have focused on...
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8
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Arumugam K, Burton NA. Disproportionation of the Uranyl(V) Coordination Complexes in Aqueous Solution through Outer-Sphere Electron Transfer. Inorg Chem 2021; 60:18832-18842. [PMID: 34847326 DOI: 10.1021/acs.inorgchem.1c02575] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Among the linear actinyl(VI/V) cations, the uranyl(V) species are particularly intriguing because they are unstable and exhibit a unique behavior to undergo H+ promoted disproportionation in aqueous solution and form stable uranyl(VI) and U(IV) complexes. This study uses density functional theory (DFT) combined with the conductor-like polarizable continuum model approach to investigate [UO2]2+/+ to [UIVO2] reduction free energies (RFEs) and explores the stability of uranyl(V) complexes in aqueous solution through computing disproportionation free energies (DFEs) for an outer-sphere electron transfer process. In addition to the aqua complex (U1), another three commonly encountered ligands such as chloride (U2), acetate (U3), and carbonate (U4) in aqueous environmental conditions are taken into account. For the U1 complex, the computed 1e- (V/IV) and 2e- (VI/IV) RFEs are in good agreement with experiments. The computed DFEs reveal that the presence of H+ is imperative for the disproportionation to take place. Although the presence of the alkali cations favors the disproportionation to some extent, they cannot fully make the reaction thermodynamically feasible. For the anionic complexes, the high negative charge does not allow for the formation of a cation-cation encounter complex due to Coulombic repulsion. Furthermore, an additional factor is the ligand exchange reaction which is also an energy-demanding step. Therefore, the current study examined the Kern-Orlemann mechanism and our results validate the mechanism based on DFT computed DFEs and propose that for the anionic complexes, an outer-sphere electron transfer is highly probable and our computed protonation free energies further support this claim.
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Affiliation(s)
- Krishnamoorthy Arumugam
- Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Neil A Burton
- Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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9
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Ortu F, Randall S, Moulding DJ, Woodward AW, Kerridge A, Meyer K, La Pierre HS, Natrajan LS. Photoluminescence of Pentavalent Uranyl Amide Complexes. J Am Chem Soc 2021; 143:13184-13194. [PMID: 34387466 PMCID: PMC8397311 DOI: 10.1021/jacs.1c05184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Pentavalent uranyl species are crucial intermediates in transformations that play a key role for the nuclear industry and have recently been demonstrated to persist in reducing biotic and abiotic aqueous environments. However, due to the inherent instability of pentavalent uranyl, little is known about its electronic structure. Herein, we report the synthesis and characterization of a series of monomeric and dimeric, pentavalent uranyl amide complexes. These synthetic efforts enable the acquisition of emission spectra of well-defined pentavalent uranyl complexes using photoluminescence techniques, which establish a unique signature to characterize its electronic structure and, potentially, its role in biological and engineered environments via emission spectroscopy.
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Affiliation(s)
- Fabrizio Ortu
- Centre for Radiochemistry Resesarch, Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K.,School of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, U.K
| | - Simon Randall
- Centre for Radiochemistry Resesarch, Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - David J Moulding
- Centre for Radiochemistry Resesarch, Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Adam W Woodward
- Centre for Radiochemistry Resesarch, Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K.,Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Andrew Kerridge
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB, U.K
| | - Karsten Meyer
- Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy, Inorganic Chemistry, Egerlandstr. 1, 91058 Erlangen, Germany
| | - Henry S La Pierre
- Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Department of Chemistry and Pharmacy, Inorganic Chemistry, Egerlandstr. 1, 91058 Erlangen, Germany.,School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States.,Nuclear and Radiological Engineering and Medical Physics Program, School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
| | - Louise S Natrajan
- Centre for Radiochemistry Resesarch, Department of Chemistry, School of Natural Sciences, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K.,Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, U.K
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10
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Evidence for ligand- and solvent-induced disproportionation of uranium(IV). Nat Commun 2021; 12:4832. [PMID: 34376682 PMCID: PMC8355312 DOI: 10.1038/s41467-021-25151-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/21/2021] [Indexed: 11/08/2022] Open
Abstract
Disproportionation, where a chemical element converts its oxidation state to two different ones, one higher and one lower, underpins the fundamental chemistry of metal ions. The overwhelming majority of uranium disproportionations involve uranium(III) and (V), with a singular example of uranium(IV) to uranium(V/III) disproportionation known, involving a nitride to imido/triflate transformation. Here, we report a conceptually opposite disproportionation of uranium(IV)-imido complexes to uranium(V)-nitride/uranium(III)-amide mixtures. This is facilitated by benzene, but not toluene, since benzene engages in a redox reaction with the uranium(III)-amide product to give uranium(IV)-amide and reduced arene. These disproportionations occur with potassium, rubidium, and cesium counter cations, but not lithium or sodium, reflecting the stability of the corresponding alkali metal-arene by-products. This reveals an exceptional level of ligand- and solvent-control over a key thermodynamic property of uranium, and is complementary to isolobal uranium(V)-oxo disproportionations, suggesting a potentially wider prevalence possibly with broad implications for the chemistry of uranium.
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11
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Molinas M, Faizova R, Brown A, Galanzew J, Schacherl B, Bartova B, Meibom KL, Vitova T, Mazzanti M, Bernier-Latmani R. Biological Reduction of a U(V)-Organic Ligand Complex. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:4753-4761. [PMID: 33705103 PMCID: PMC8154365 DOI: 10.1021/acs.est.0c06633] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 02/24/2021] [Accepted: 03/01/2021] [Indexed: 05/20/2023]
Abstract
Metal-reducing microorganisms such as Shewanella oneidensis MR-1 reduce highly soluble species of hexavalent uranyl (U(VI)) to less mobile tetravalent uranium (U(IV)) compounds. The biologically mediated immobilization of U(VI) is being considered for the remediation of U contamination. However, the mechanistic underpinnings of biological U(VI) reduction remain unresolved. It has become clear that a first electron transfer occurs to form pentavalent (U(V)) intermediates, but it has not been definitively established whether a second one-electron transfer can occur or if disproportionation of U(V) is required. Here, we utilize the unusual properties of dpaea2- ((dpaeaH2═bis(pyridyl-6-methyl-2-carboxylate)-ethylamine)), a ligand forming a stable soluble aqueous complex with U(V), and investigate the reduction of U(VI)-dpaea and U(V)-dpaea by S. oneidensis MR-1. We establish U speciation through time by separating U(VI) from U(IV) by ion exchange chromatography and characterize the reaction end-products using U M4-edge high resolution X-ray absorption near-edge structure (HR-XANES) spectroscopy. We document the reduction of solid phase U(VI)-dpaea to aqueous U(V)-dpaea but, most importantly, demonstrate that of U(V)-dpaea to U(IV). This work establishes the potential for biological reduction of U(V) bound to a stabilizing ligand. Thus, further work is warranted to investigate the possible persistence of U(V)-organic complexes followed by their bioreduction in environmental systems.
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Affiliation(s)
- Margaux Molinas
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
| | - Radmila Faizova
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
| | - Ashley Brown
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
| | - Jurij Galanzew
- Karlsruhe
Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), P.O. 3640, D-76021Karlsruhe, Germany
| | - Bianca Schacherl
- Karlsruhe
Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), P.O. 3640, D-76021Karlsruhe, Germany
| | - Barbora Bartova
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
| | - Karin L. Meibom
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
| | - Tonya Vitova
- Karlsruhe
Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), P.O. 3640, D-76021Karlsruhe, Germany
| | - Marinella Mazzanti
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
| | - Rizlan Bernier-Latmani
- Environmental
Microbiology Laboratory, and Group of Coordination Chemistry, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Lausanne 1015, Switzerland
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12
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Faizova R, Fadaei‐Tirani F, Chauvin A, Mazzanti M. Synthesis and Characterization of Water Stable Uranyl(V) Complexes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Radmila Faizova
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Farzaneh Fadaei‐Tirani
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Anne‐Sophie Chauvin
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Marinella Mazzanti
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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13
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Faizova R, Fadaei‐Tirani F, Chauvin A, Mazzanti M. Synthesis and Characterization of Water Stable Uranyl(V) Complexes. Angew Chem Int Ed Engl 2021; 60:8227-8235. [DOI: 10.1002/anie.202016123] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/04/2021] [Indexed: 12/13/2022]
Affiliation(s)
- Radmila Faizova
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Farzaneh Fadaei‐Tirani
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Anne‐Sophie Chauvin
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Marinella Mazzanti
- Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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14
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Hu SX, Zhang P, Lu E, Zhang P. Decisive Role of 5f-Orbital Covalence in the Structure and Stability of Pentavalent Transuranic Oxo [M 6O 8] Clusters. Inorg Chem 2020; 59:18068-18077. [PMID: 33287539 DOI: 10.1021/acs.inorgchem.0c02539] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Actinide metal oxo clusters are of vital importance in actinide chemistry, as well as in environmental and materials sciences. They are ubiquitous in both aqueous and nonaqueous phases and play key roles in nuclear materials (e.g., nuclear fuel) and nuclear waste management. Despite their importance, our structural understanding of the actinide metal oxo clusters, particularly the transuranic ones, is very limited because of experimental challenges such as high radioactivity. Herein we report a systematic theoretical study on the structures and stabilities of seven actinide metal oxo-hydroxo clusters [AnIV6O4(OH)4L12] (1-An; An = Th-Cm; L = O2CH-) along with their group 4 (Ti, Zr, Hf, Rf) and lanthanide (Ce) counterparts [MIV6O4(OH)4L12] (1-M). The work shows the Td-symmetric structures of all of the 1-An/M clusters and suggests the positions of the -OH functional groups, which are experimentally challenging to determine. Furthermore, by removing six electrons from 1-An, we found that oxidation could happen on the AnIV metal ions, producing [AnV6O4(OH)4L12]6+ (2-An; An = Pa, U, Np), or on the O2- and OH- ligands, producing [AnIV6(O•-)4(OH•)2(OH)2L12]6+ (3-An; An = Pu, Am, Cm). On the basis of 2-An, we constructed a series of tetravalent and pentavalent actinide metal oxo clusters [AnIV6O14]4- (4-An) and [AnV6O14]2+ (5-An), which proves the feasibility of the highly important pentavalent actinyl clusters, demonstrates the f orbital's structure-directing role in the formation of linear [O≡AnV═O]+ actinyl ions, and expands the concept of actinyl-actinyl interaction into pentavalent transuranic actinyl clusters.
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Affiliation(s)
- Shu-Xian Hu
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China.,Beijing Computational Science Research Center, Beijing 100193, China
| | - Peng Zhang
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Erli Lu
- School of Natural and Environmental Sciences, Newcastle University, Newcastle NE1 7RU, U.K
| | - Ping Zhang
- Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
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15
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Maurice R, Dau PD, Hodée M, Renault E, Gibson JK. Controlling Cation‐Cation Interactions in Uranyl Coordination Dimers by Varying the Length of the Dicarboxylate Linker. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Rémi Maurice
- SUBATECH, UMR CNRS 6457 IN2P3/IMT Atlantique/Université de Nantes 4 rue Alfred Kastler, BP 20722 44307 Nantes Cedex 3 France
| | - Phuong D. Dau
- Chemical Sciences Division Lawrence Berkeley National Laboratory 94720 Berkeley California United States
| | | | | | - John K. Gibson
- Chemical Sciences Division Lawrence Berkeley National Laboratory 94720 Berkeley California United States
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16
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Petrus E, Segado M, Bandeira NAG, Bo C. Unveiling a Photoinduced Hydrogen Evolution Reaction Mechanism via the Concerted Formation of Uranyl Peroxide. Inorg Chem 2020; 59:8353-8360. [PMID: 32496796 DOI: 10.1021/acs.inorgchem.0c00757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We present a density functional theory study for the photochemical water oxidation reaction promoted by uranyl nitrate upon sunlight radiation. First, we explored the most stable uranyl complex in the absence of light. The reaction in a dark environmen proceeds through the condensation of uranyl monomers to form dimeric hydroxo-bridged species, which is the first step toward a hydrogen evolution reaction (HER). We found a triplet-state-driven mechanism that leads to the formation of uranyl peroxide and hydrogen gas. To describe in detail this reaction path, we characterized the singlet and triplet low-lying states of the dimeric hydroxo-bridged species, including minima, transition states, minimal energy crossing points, and adiabatic energies. Our computational results provide mechanistic insights that are in good agreement with the experimental data available.
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Affiliation(s)
- Enric Petrus
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Mireia Segado
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Nuno A G Bandeira
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, 43007 Tarragona, Spain.,BioISI - Biosystems & Integrative Sciences Institute, C8, Faculty Sciences, University of Lisbon, Campo Grande, 1749-016 Lisboa, Portugal
| | - Carles Bo
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, 43007 Tarragona, Spain.,Departament de Química Física I Inorgànica, Universitat Roviri i Virgili, Marcel·lí Domingo s/n, 43007 Tarragona, Spain
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17
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Carlson RK, Cawkwell MJ, Batista ER, Yang P. Tight-Binding Modeling of Uranium in an Aqueous Environment. J Chem Theory Comput 2020; 16:3073-3083. [DOI: 10.1021/acs.jctc.0c00089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rebecca K. Carlson
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - M. J. Cawkwell
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Enrique R. Batista
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Ping Yang
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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18
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Zegke M, Zhang X, Pidchenko I, Hlina JA, Lord RM, Purkis J, Nichol GS, Magnani N, Schreckenbach G, Vitova T, Love JB, Arnold PL. Differential uranyl(v) oxo-group bonding between the uranium and metal cations from groups 1, 2, 4, and 12; a high energy resolution X-ray absorption, computational, and synthetic study. Chem Sci 2019; 10:9740-9751. [PMID: 32055343 PMCID: PMC6993744 DOI: 10.1039/c8sc05717f] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 08/26/2019] [Indexed: 11/21/2022] Open
Abstract
Uranyl Pacman takes them all: the bonding of s- and d-block cations to uranyl is compared by experiment, spectroscopy and theory.
The uranyl(vi) ‘Pacman’ complex [(UO2)(py)(H2L)] A (L = polypyrrolic Schiff-base macrocycle) is reduced by Cp2Ti(η2-Me3SiC
Created by potrace 1.16, written by Peter Selinger 2001-2019
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CSiMe3) and [Cp2TiCl]2 to oxo-titanated uranyl(v) complexes [(py)(Cp2TiIIIOUO)(py)(H2L)] 1 and [(ClCp2TiIVOUO)(py)(H2L)] 2. Combination of ZrII and ZrIV synthons with A yields the first ZrIV–uranyl(v) complex, [(ClCp2ZrOUO)(py)(H2L)] 3. Similarly, combinations of Ae0 and AeII synthons (Ae = alkaline earth) afford the mono-oxo metalated uranyl(v) complexes [(py)2(ClMgOUO)(py)(H2L)] 4, [(py)2(thf)2(ICaOUO)(py) (H2L)] 5; the zinc complexes [(py)2(XZnOUO)(py)(H2L)] (X = Cl 6, I 7) are formed in a similar manner. In contrast, the direct reactions of Rb or Cs metal with A generate the first mono-rubidiated and mono-caesiated uranyl(v) complexes; monomeric [(py)3(RbOUO)(py)(H2L)] 8 and hexameric [(MOUO)(py)(H2L)]6 (M = Rb 8b or Cs 9). In these uranyl(v) complexes, the pyrrole N–H atoms show strengthened hydrogen-bonding interactions with the endo-oxos, classified computationally as moderate-strength hydrogen bonds. Computational DFT MO (density functional theory molecular orbital) and EDA (energy decomposition analysis), uranium M4 edge HR-XANES (High Energy Resolution X-ray Absorption Near Edge Structure) and 3d4f RIXS (Resonant Inelastic X-ray Scattering) have been used (the latter two for the first time for uranyl(v) in 7 (ZnI)) to compare the covalent character in the UV–O and O–M bonds and show the 5f orbitals in uranyl(vi) complex A are unexpectedly more delocalised than in the uranyl(v) 7 (ZnI) complex. The Oexo–Zn bonds have a larger covalent contribution compared to the Mg–Oexo/Ca–Oexo bonds, and more covalency is found in the U–Oexo bond in 7 (ZnI), in agreement with the calculations.
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Affiliation(s)
- Markus Zegke
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
| | - Xiaobin Zhang
- Department of Chemistry , University of Manitoba , Winnipeg , MB R3T 2N2 , Canada . ; ; Tel: +1-204-474-6261
| | - Ivan Pidchenko
- Institute for Nuclear Waste Disposal (INE) , Karlsruhe Institute of Technology (KIT) , P.O. Box 3640 , 76021 Karlsruhe , Germany .
| | - Johann A Hlina
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
| | - Rianne M Lord
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
| | - Jamie Purkis
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
| | - Gary S Nichol
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
| | - Nicola Magnani
- Institute for Transuranium Elements , Joint Research Centre , European Commission , PO Box 2340 , 76125 Karlsruhe , Germany
| | - Georg Schreckenbach
- Department of Chemistry , University of Manitoba , Winnipeg , MB R3T 2N2 , Canada . ; ; Tel: +1-204-474-6261
| | - Tonya Vitova
- Institute for Nuclear Waste Disposal (INE) , Karlsruhe Institute of Technology (KIT) , P.O. Box 3640 , 76021 Karlsruhe , Germany .
| | - Jason B Love
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
| | - Polly L Arnold
- EaStCHEM School of Chemistry , The University of Edinburgh , David Brewster Road , Edinburgh EH9 3FJ , UK . ; ; ; Tel: +44(0) 130 650 5429
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19
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Bower WR, Morris K, Livens FR, Mosselmans JFW, Fallon CM, Fuller AJ, Natrajan L, Boothman C, Lloyd JR, Utsunomiya S, Grolimund D, Ferreira Sanchez D, Jilbert T, Parker J, Neill TS, Law GTW. Metaschoepite Dissolution in Sediment Column Systems-Implications for Uranium Speciation and Transport. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:9915-9925. [PMID: 31317743 DOI: 10.1021/acs.est.9b02292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Metaschoepite is commonly found in U-contaminated environments and metaschoepite-bearing wastes may be managed via shallow or deep disposal. Understanding metaschoepite dissolution and tracking the fate of any liberated U is thus important. Here, discrete horizons of metaschoepite (UO3·nH2O) particles were emplaced in flowing sediment/groundwater columns representative of the UK Sellafield Ltd. site. The column systems either remained oxic or became anoxic due to electron donor additions, and the columns were sacrificed after 6- and 12-months for analysis. Solution chemistry, extractions, and bulk and micro/nano-focus X-ray spectroscopies were used to track changes in U distribution and behavior. In the oxic columns, U migration was extensive, with UO22+ identified in effluents after 6-months of reaction using fluorescence spectroscopy. Unusually, in the electron-donor amended columns, during microbially mediated sulfate reduction, significant amounts of UO2-like colloids (>60% of the added U) were found in the effluents using TEM. XAS analysis of the U remaining associated with the reduced sediments confirmed the presence of trace U(VI), noncrystalline U(IV), and biogenic UO2, with UO2 becoming more dominant with time. This study highlights the potential for U(IV) colloid production from U(VI) solids under reducing conditions and the complexity of U biogeochemistry in dynamic systems.
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Affiliation(s)
- William R Bower
- Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Manchester , U.K. , M13 9PL
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
- Radiochemistry Unit, Department of Chemistry , The University of Helsinki , Helsinki , Finland , 00014
| | - Katherine Morris
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
| | - Francis R Livens
- Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Manchester , U.K. , M13 9PL
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
| | | | - Connaugh M Fallon
- Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Manchester , U.K. , M13 9PL
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
- Radiochemistry Unit, Department of Chemistry , The University of Helsinki , Helsinki , Finland , 00014
| | - Adam J Fuller
- Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Manchester , U.K. , M13 9PL
| | - Louise Natrajan
- Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Manchester , U.K. , M13 9PL
| | - Christopher Boothman
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
| | - Jonathan R Lloyd
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
| | - Satoshi Utsunomiya
- Kyushu University , Department of Chemistry , 744 Motooka , Nishi-ku , Fukuoka Japan , 819-0395
| | - Daniel Grolimund
- Swiss Light Source , Paul Scherrer Institute , Villigen , Switzerland , 5232
| | | | - Tom Jilbert
- Ecosystems and Environmental Research Programme, Faculty of Biological and Environmental Sciences , The University of Helsinki , Helsinki , Finland , 00014
| | - Julia Parker
- Diamond Light Source , Harwell Science and Innovation Campus , Didcot , U.K. , OX11 0DE
| | - Thomas S Neill
- Research Centre for Radwaste Disposal and Williamson Research Centre, School of Earth and Environmental Sciences , The University of Manchester , Manchester , U.K. , M13 9PL
| | - Gareth T W Law
- Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Manchester , U.K. , M13 9PL
- Radiochemistry Unit, Department of Chemistry , The University of Helsinki , Helsinki , Finland , 00014
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20
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Cowie BE, Purkis JM, Austin J, Love JB, Arnold PL. Thermal and Photochemical Reduction and Functionalization Chemistry of the Uranyl Dication, [UVIO2]2+. Chem Rev 2019; 119:10595-10637. [DOI: 10.1021/acs.chemrev.9b00048] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Bradley E. Cowie
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, The King’s Buildings, Edinburgh EH9 3FJ, U.K
| | - Jamie M. Purkis
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, The King’s Buildings, Edinburgh EH9 3FJ, U.K
| | - Jonathan Austin
- National Nuclear Laboratory, Chadwick House,
Warrington Road, Birchwood Park, Warrington WA3 6AE, U.K
| | - Jason B. Love
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, The King’s Buildings, Edinburgh EH9 3FJ, U.K
| | - Polly L. Arnold
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, The King’s Buildings, Edinburgh EH9 3FJ, U.K
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21
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Hu SX, Jian J, Li J, Gibson JK. Destruction of the Uranyl Moiety in a U(V) “Cation–Cation” Interaction. Inorg Chem 2019; 58:10148-10159. [DOI: 10.1021/acs.inorgchem.9b01265] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shu-Xian Hu
- Beijing Computational Science Research Center, Beijing 100193, China
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Jiwen Jian
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - John K. Gibson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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22
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George K, Muller J, Berthon L, Berthon C, Guillaumont D, Vitorica-Yrezabal IJ, Stafford HV, Natrajan LS, Tamain C. Exploring the Coordination of Plutonium and Mixed Plutonyl-Uranyl Complexes of Imidodiphosphinates. Inorg Chem 2019; 58:6904-6917. [PMID: 31025862 DOI: 10.1021/acs.inorgchem.9b00346] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The coordination chemistry of plutonium(IV) and plutonium(VI) with the complexing agents tetraphenyl and tetra-isopropyl imidodiphosphinate (TPIP- and TIPIP-) is reported. Treatment of sodium tetraphenylimidodiphosphinate (NaTPIP) and its related counterpart with peripheral isopropyl groups (NaTIPIP) with [NBu4]2[PuIV(NO3)6] yields the respective PuIV complexes [Pu(TPIP)3(NO3)] and [Pu(TIPIP)2(NO3)2] + [PuIV(TIPIP)3(NO3)]. Similarly, the reactions of NaTPIP and NaTIPIP with a Pu(VI) nitrate solution lead to the formation of [PuO2(HTIPIP)2(H2O)][NO3]2, which incorporates a protonated bidentate TIPIP- ligand, and [PuO2(TPIP)(HTPIP)(NO3)], where the protonated HTPIP ligand is bound in a monodentate fashion. Finally, a mixed U(VI)/Pu(VI) compound, [(UO2/PuO2)(TPIP)(HTPIP)(NO3)], is reported. All these actinyl complexes remain in the +VI oxidation state in solution over several weeks. The resultant complexes have been characterized using a combination of X-ray structural studies, NMR, optical, vibrational spectroscopies, and electrospray ionization mass spectrometry. The influence of the R-group (R = phenyl or iPr) on the nature of the complex is discussed with the help of DFT studies.
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Affiliation(s)
- Kathryn George
- The Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
| | - Julie Muller
- Nuclear Energy Division, RadioChemistry & Processes Department , CEA , Bagnols-sur-Cèze F-30207 , France
| | - Laurence Berthon
- Nuclear Energy Division, RadioChemistry & Processes Department , CEA , Bagnols-sur-Cèze F-30207 , France
| | - Claude Berthon
- Nuclear Energy Division, RadioChemistry & Processes Department , CEA , Bagnols-sur-Cèze F-30207 , France
| | - Dominique Guillaumont
- Nuclear Energy Division, RadioChemistry & Processes Department , CEA , Bagnols-sur-Cèze F-30207 , France
| | - Iñigo J Vitorica-Yrezabal
- The Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
| | - H Victoria Stafford
- The Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
| | - Louise S Natrajan
- The Centre for Radiochemistry Research, School of Chemistry , The University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom
| | - Christelle Tamain
- Nuclear Energy Division, RadioChemistry & Processes Department , CEA , Bagnols-sur-Cèze F-30207 , France
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23
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Arumugam K, Burton NA. Density functional theory (DFT) calculations of VI/V reduction potentials of uranyl coordination complexes in non-aqueous solutions. Phys Chem Chem Phys 2019; 21:3227-3241. [PMID: 30681090 DOI: 10.1039/c8cp05412f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Of particular interest within the +6 uranium complexes is the linear uranyl(vi) cation and it forms numerous coordination complexes in solution and exhibits incongruent redox behavior depending on coordinating ligands. In this study, to determine the reduction potentials of uranyl complexes in non-aqueous solutions, a hybrid density functional theory (DFT) approach was used in which two different DFT functionals, B3LYP and M06, were applied. Bulk solvent effects were invoked through the conductor-like polarizable continuum model. The solute cavities were described with the united-atom Kohn-Sham (UAKS) cavity definition. Inside the cavity the dielectric constant matches the value of a vacuum and outside the cavity the dielectric constant value is the same as that of the solvent of interest, for example, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), dichloromethane (DCM), acetonitrile and pyridine. With the help of the Nernst equation the calculated reduction potentials with respect to the ferrocene (Fc) reference electrode are converted into reduction free energies (RFEs). Uranyl complexes of organic ligands which range from mono- to hexa-dentate coordination modes were investigated in non-aqueous solutions of DMSO, DMF, DCM, acetonitrile and pyridine solutions. The effect of the spin-orbit correction and the reference electrode correction on the RFEs and various methods such as the direct method and the isodesmic reaction model were explored. Overall, our computational determination of RFEs of uranyl complexes in various non-aqueous solutions demonstrates that the RFEs can be obtained within ∼0.2 eV of experimental values.
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Affiliation(s)
- Krishnamoorthy Arumugam
- School of Chemistry, The University of Manchester, Brunswick Street, Manchester M13 9PL, UK.
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24
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Feng R, Glendening ED, Peterson KA. Actinyl cation–cation interactions in the gas phase: an accurate thermochemical study. Phys Chem Chem Phys 2019; 21:7953-7964. [DOI: 10.1039/c9cp00760a] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Accurate coupled cluster calculations of actinyl cation–cation interactions suggest significant gas phase kinetic stabilities that correlate well with known species in condensed phases.
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Affiliation(s)
- Rulin Feng
- Department of Chemistry
- Washington State University
- Pullman
- USA
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25
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Nuzzo S, van Leusen J, Twamley B, Platts JA, Kögerler P, Baker RJ. Oxidation of uranium(iv) thiocyanate complexes: cation–cation interactions in mixed-valent uranium coordination chains. Dalton Trans 2019; 48:6704-6708. [DOI: 10.1039/c9dt01005j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Oxidation of Cs4[U(NCS)8] in different solvents results in two mixed-valent uranium compounds. Spectroscopic, magnetic and computational data support a unique [UIVUVUIV][UVI] oxidation state assignment in [U(DMF)8(μ-O)U(NCS)5(μ-O)U(DMF)7(NCS)][UO2(NCS)5].
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Affiliation(s)
- Stefano Nuzzo
- School of Chemistry
- University of Dublin
- Trinity College
- Dublin 2
- Ireland
| | - Jan van Leusen
- Institute of Inorganic Chemistry
- RWTH Aachen University
- D-52074 Aachen
- Germany
| | - Brendan Twamley
- School of Chemistry
- University of Dublin
- Trinity College
- Dublin 2
- Ireland
| | | | - Paul Kögerler
- Institute of Inorganic Chemistry
- RWTH Aachen University
- D-52074 Aachen
- Germany
| | - Robert J. Baker
- School of Chemistry
- University of Dublin
- Trinity College
- Dublin 2
- Ireland
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26
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Shilov VP, Gogolev AV, Fedoseev AM. Influence of the Redox Potential and Charge of f Element Ions on the Kinetics of Reactions Involving Them. RADIOCHEMISTRY 2018. [DOI: 10.1134/s1066362218060012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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27
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Hixon AE, Powell BA. Plutonium environmental chemistry: mechanisms for the surface-mediated reduction of Pu(v/vi). ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2018; 20:1306-1322. [PMID: 30251720 DOI: 10.1039/c7em00369b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In recent decades, interest in plutonium mobility has increased significantly due to the need of the United States, as well as other nations, to deal with commercial spent nuclear fuel, nuclear weapons disarmament, and the remediation of locations contaminated by nuclear weapons testing and production. Although there is a global consensus that geologic disposal is the safest existing approach to dealing with spent nuclear fuel and high-level nuclear waste, only a few nations are moving towards implementing a geologic repository due to technical and political barriers. Understanding the factors that affect the mobility of plutonium in the subsurface environment is critical to support the development of such repositories. The importance of redox chemistry in determining plutonium mobility cannot be understated. While Pu(iv) is generally assumed to be immobile in the subsurface environment due to sorption or precipitation, Pu(v) tends to be mobile due to its relatively low effective charge and weak complex formation. This review highlights one particularly important aspect of plutonium behaviour at the mineral-water interface-the concept of surface-mediated reduction, which describes the reduction of plutonium on a mineral surface. It provides a conceptual model for and evidence supporting or refuting each proposed mechanism for surface-mediated reduction including (i) radiolysis at the mineral surface, (ii) electron transfer via ferrous iron or manganese in the mineral structure, (iii) electron shuttling due to the semiconducting properties of the mineral, (iv) disproportionation of Pu(v), (v) facilitation by proton exchange sites, (vi) stabilisation of Pu(iv) due to the increased concentration gradient within the electrical double layer, and (vii) a Nernstian favourability of Pu(iv) surface complexes and colloids. It also provides new perspectives on future research directions.
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Affiliation(s)
- Amy E Hixon
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.
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28
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Faizova R, White S, Scopelliti R, Mazzanti M. The effect of iron binding on uranyl(v) stability. Chem Sci 2018; 9:7520-7527. [PMID: 30319752 PMCID: PMC6179087 DOI: 10.1039/c8sc02099j] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 07/31/2018] [Indexed: 11/21/2022] Open
Abstract
The tripodal heptadentate Schiff base trensal3– ligand allowed the synthesis and characterization of stable uranyl(v) complexes presenting UO2+···K+ or UO2+···Fe2+ cation–cation interactions. The presence of Fe2+ bound to the uranyl(v) oxygen leads to increased stability with respect to proton induced disproportionation and to an increased range of stability of the uranyl(v) species with respect both to oxidation and reduction reactions.
Here we report the effect of UO2+···Fe2+ cation–cation interactions on the redox properties of uranyl(v) complexes and on their stability with respect to proton induced disproportionation. The tripodal heptadentate Schiff base trensal3– ligand allowed the synthesis and characterization of the uranyl(vi) complexes [UO2(trensal)K], 1 and [UO2(Htrensal)], 2 and of uranyl(v) complexes presenting UO2+···K+ or UO2+···Fe2+ cation–cation interactions ([UO2(trensal)K]K, 3, [UO2(trensal)] [K(2.2.2crypt)][K(2.2.2crypt)], 4, [UO2(trensal)Fe(py)3], 6). The uranyl(v) complexes show similar stability in pyridine solution, but the presence of Fe2+ bound to the uranyl(v) oxygen leads to increased stability with respect to proton induced disproportionation through the formation of a stable Fe2+–UO2+–U4+ intermediate ([UO2(trensal)Fe(py)3U(trensal)]I, 7) upon addition of 2 eq. of PyHCl to 6. The addition of 2 eq. of PyHCl to 3 results in the immediate formation of U(iv) and UO22+ compounds. The presence of an additional UO2+ bound Fe2+ in [(UO2(trensal)Fe(py)3)2Fe(py)3]I2, 8, does not lead to increased stability. Redox reactivity and cyclic voltammetry studies also show an increased range of stability of the uranyl(v) species in the presence of Fe2+ with respect both to oxidation and reduction reactions, while the presence of a proton in complex 2 results in a smaller stability range for the uranyl(v) species. Cyclic voltammetry studies also show that the presence of a Fe2+ cation bound through one trensal3– arm in the trinuclear complex [{UO2(trensal)}2Fe], 5 does not lead to increased redox stability of the uranyl(v) showing the important role of UO2+···Fe2+ cation–cation interactions in increasing the stability of uranyl(v). These results provide an important insight into the role that iron binding may play in stabilizing uranyl(v) compounds in the environmental mineral-mediated reduction of uranium(vi).
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Affiliation(s)
- Radmila Faizova
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland .
| | - Sarah White
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland .
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland .
| | - Marinella Mazzanti
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland .
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29
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Faizova R, Scopelliti R, Chauvin AS, Mazzanti M. Synthesis and Characterization of a Water Stable Uranyl(V) Complex. J Am Chem Soc 2018; 140:13554-13557. [PMID: 30289696 DOI: 10.1021/jacs.8b07885] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have identified a polydentate aminocarboxylate ligand that stabilizes uranyl(V) in water. The mononuclear [UO2(dpaea)]X, (dpaeaH2 = Bis(pyridyl-6-methyl-2-carboxylate)-ethylamine; X = CoCp2*+ or X = K(2.2.2.cryptand) complexes have been isolated from anaerobic organic solution, crystallographically and spectroscopically characterized both in water and organic solution. These complexes disproportionate at pH ≤ 6, but are stable in anaerobic water at pH 7-10 for several days.
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Affiliation(s)
- Radmila Faizova
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
| | - Anne-Sophie Chauvin
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
| | - Marinella Mazzanti
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
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30
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Smith PA, Hickam SM, Szymanowski JES, Burns PC. Mixed-Valent Cyanoplatinates Featuring Neptunyl-Neptunyl Cation-Cation Interactions. Inorg Chem 2018; 57:9504-9514. [PMID: 30009590 DOI: 10.1021/acs.inorgchem.8b01500] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The tetracyanoplatinate ligand was employed in synthesizing the first neptunyl cyanoplatinate complexes. Results indicate in situ oxidation of Pt(II) by Np(V/VI) to form mixed-valent Pt-Pt stacked columnar chains linked by cation-cation interaction induced chains of Np(V) polyhedra into a two-dimensional sheet structure. The Pt-Pt stacking distances of 3.04-3.05 Å are the longest reported columnar platinophilic interactions among mixed-valent tetracyanoplatinate structures. These complexes further illustrate the marked chemical differences and structural diversity of solid-state Np(V) coordination complexes with regard to Np(VI) and U(VI).
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Affiliation(s)
- Philip A Smith
- Department of Civil and Environmental Engineering and Earth Sciences , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Sarah M Hickam
- Department of Civil and Environmental Engineering and Earth Sciences , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Jennifer E S Szymanowski
- Department of Civil and Environmental Engineering and Earth Sciences , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Peter C Burns
- Department of Civil and Environmental Engineering and Earth Sciences , University of Notre Dame , Notre Dame , Indiana 46556 , United States.,Department of Chemistry and Biochemistry , University of Notre Dame , Notre Dame , Indiana 46556 , United States
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31
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Abstract
Intermolecular interactions between the oxo group of an actinyl cation and other metal cations (i.e., cation-cation interactions) are dependent on the strength of the actinyl bond. These cation-cation interactions are prominently observed for the neptunyl cation [Np(V)O2]+ and are sufficiently stable enough to explore using a variety of chemical techniques. Herein, we investigate these intermolecular interactions in the neptunyl 18-crown-6 system, because this macrocyclic ligand provides both stable coordination and the proper sterics to engage the oxo group in bonding with both low-valent metal cations and neighboring neptunyl units. We report the structural and spectroscopic characterization of five neptunyl, [Np(V,VI)O2]+,2+, compounds: Np1a ([NpO2(18-crown-6)]ClO4), Np1b ([NpO2(18-crown-6)]AuCl4), Na-Np ([Np(V)O2(18-crown-6)(Na(H2O)(18-crown-6)][Np(VI)O2Cl4], Np-Np ([NpO2(18-crown-6)](NpO2Cl2NO3)], and Np-Cl (NpO2Cl(H2O)1.75). Each of these compounds were prepared from the ambient reactions of Np(V) in HX (where X = Cl, NO3) with the 18-crown-6 ether molecule. Structural information obtained from single-crystal X-ray diffraction data was paired with solid-state and solution Raman spectroscopy to provide information on the interaction of the neptunyl oxo atom with neighboring cations. Neptunyl (Np═O) bond lengths are not perturbed upon interaction with the Na+ cation (Na-Np), but elongation is observed upon formation of a neptunyl-neptunyl interaction (Np-Np). This is also the first structurally characterized isolated, molecular complex that contains a simple T-shaped neptunyl-neptunyl interaction. Raman spectroscopy indicates little perturbation to the neptunyl bond until the formation of the neptunyl-neptunyl motif, which also results in activation of the ν3 asymmetric stretch. Additional spectroscopic studies indicated that the neptunyl 18-crown-6 inclusion complexes form in solution and persist in the presence of other low-valence cations.
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Affiliation(s)
- Madeline Basile
- Department of Chemistry , University of Iowa , Iowa City , Iowa 52242 , United States
| | - Erica Cole
- Department of Chemistry , University of Iowa , Iowa City , Iowa 52242 , United States
| | - Tori Z Forbes
- Department of Chemistry , University of Iowa , Iowa City , Iowa 52242 , United States
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32
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Kretzschmar J, Haubitz T, Hübner R, Weiss S, Husar R, Brendler V, Stumpf T. Network-like arrangement of mixed-valence uranium oxide nanoparticles after glutathione-induced reduction of uranium(vi). Chem Commun (Camb) 2018; 54:8697-8700. [DOI: 10.1039/c8cc02070a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
2–5 nm UO2+x nanocrystals yielded under near-neutral conditions arrange as 20–40 nm chain-like building blocks, and finally form network-like aggregates.
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Affiliation(s)
- Jerome Kretzschmar
- Institute of Resource Ecology
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
| | - Toni Haubitz
- Institute of Resource Ecology
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
- Institute of Chemistry
| | - René Hübner
- Institute of Ion Beam Physics and Materials Research
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
| | - Stephan Weiss
- Institute of Resource Ecology
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
| | - Richard Husar
- Institute of Resource Ecology
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
| | - Vinzenz Brendler
- Institute of Resource Ecology
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
| | - Thorsten Stumpf
- Institute of Resource Ecology
- Helmholtz-Zentrum Dresden-Rossendorf
- 01328 Dresden
- Germany
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33
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Carter KP, Jian J, Pyrch MM, Forbes TZ, Eaton TM, Abergel RJ, de Jong WA, Gibson JK. Reductive activation of neptunyl and plutonyl oxo species with a hydroxypyridinone chelating ligand. Chem Commun (Camb) 2018; 54:10698-10701. [DOI: 10.1039/c8cc05626a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neptunyl(vi) and plutonyl(vi) oxo-activation with reduction to tetravalent hydroxides was investigated in gas and condensed phases, and by density functional theory.
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Affiliation(s)
- Korey P. Carter
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - Jiwen Jian
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | | | | | - Teresa M. Eaton
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - Rebecca J. Abergel
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Nuclear Engineering
| | - Wibe A. de Jong
- Computational Research Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - John K. Gibson
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
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34
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Collins RN, Rosso KM. Mechanisms and Rates of U(VI) Reduction by Fe(II) in Homogeneous Aqueous Solution and the Role of U(V) Disproportionation. J Phys Chem A 2017; 121:6603-6613. [PMID: 28809500 DOI: 10.1021/acs.jpca.7b05965] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Molecular-level pathways in the aqueous redox transformation of uranium by iron remain unclear, despite the importance of this knowledge for predicting uranium transport and distribution in natural and engineered environments. As the relative importance of homogeneous versus heterogeneous pathways is difficult to probe experimentally, here we apply computational molecular simulation to isolate rates of key one electron transfer reactions in the homogeneous pathway. By comparison to experimental observations the role of the heterogeneous pathway also becomes clear. Density functional theory (DFT) and Marcus theory calculations for all primary monomeric species at pH values ≤7 show for UO22+ and its hydrolysis species UO2OH+ and UO2(OH)20 that reduction by Fe2+ is thermodynamically favorable, though kinetically limited for UO22+. An inner-sphere encounter complex between UO2OH+ and Fe2+ was the most stable for the first hydrolysis species and displayed an electron transfer rate constant ket = 4.3 × 103 s-1. Three stable inner- and outer-sphere encounter complexes between UO2(OH)20 and Fe2+ were found, with electron transfer rate constants ranging from ket = 7.6 × 102 to 7.2 × 104 s-1. Homogeneous reduction of these U(VI) hydrolysis species to U(V) is, therefore, predicted to be facile. In contrast, homogeneous reduction of UO2+ by Fe2+ was found to be thermodynamically unfavorable, suggesting the possible importance of U(V)-U(V) disproportionation as a route to U(IV). Calculations on homogeneous disproportionation, however, while yielding a stable outer-sphere U(V)-U(V) encounter complex, indicate that this electron transfer reaction is not feasible at circumneutral pH. Protonation of both axial O atoms of acceptor U(V) (i.e., by H3O+) was found to be a prerequisite to stabilize U(IV), consistent with the experimental observation that the rate of this reaction is inversely correlated with pH. Thus, despite prevailing notions that U(V) is rapidly eliminated by homogeneous disproportionation, this pathway is irrelevant at environmental conditions.
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Affiliation(s)
- Richard N Collins
- UNSW Water Research Centre, School of Civil and Environmental Engineering, UNSW Australia , Sydney, NSW, Australia 2052
| | - Kevin M Rosso
- UNSW Water Research Centre, School of Civil and Environmental Engineering, UNSW Australia , Sydney, NSW, Australia 2052.,Physical Sciences Division, Pacific Northwest National Laboratory , Richland, Washington 99336, United States
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35
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Dumpala RMR, Rawat N, Tomar BS. Stability, speciation and spectral properties of NpO 2+ complexes with pyridine monocarboxylates in aqueous solution. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 181:13-22. [PMID: 28314204 DOI: 10.1016/j.saa.2017.03.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 02/24/2017] [Accepted: 03/04/2017] [Indexed: 06/06/2023]
Abstract
Neptunyl ion as NpO2+ is the least reacting and most mobile radioactive species among all the actinides. The picolinic acid used for decontamination is co-disposed along with the radioactive waste. Thus, in long term storage of HLW, there is high possibility of interaction of actinides and long lived fission products with the picolinate and can cause migration. The complexation of NpO2+ with the three structural isomers of pyridine monocarboxylates provides an insight to explore the role of hetero atom (nitrogen) with respect to key binding moiety (carboxylate). In the present study, the log β values, speciation and spectral properties of NpO2+ complexes with pyridine monocarboxylates viz. picolinate, nicotinate and isonicotinate, have been studied at 298K in 0.1M NaClO4 medium using spectrophotometry. The complexation reactions involving protonated ligands are always accompanied by protonation/deprotonation process; thus, the protonation constants of all the three pyridine monocarboxylates under same conditions were also determined by potentiometry. The spectrophotometric data analysis for complexation of NpO2+ with pyridine monocarboxylates indicated the presence of ML and ML2 complexes with log β values of 2.96±0.04, 5.67±0.08 for picolinate, 1.34±0.09, 1.65±0.12 for nicotinate and 1.52±0.04, 2.39±0.06 for isonicotinate. The higher values of log β for picolinate were attributed to chelation while in other two isomers, the binding is through carboxylate group only. Density Functional Theory (DFT) calculations were carried out to get optimized geometries and electrostatic charges on various atoms of the complexes and free pyridine monocarboxylates to support the experimental data. The higher stability of NpO2+ nicotinate and isonicotinate complexes compared to simple carboxylates and the difference in log β between the two is due to the charge polarization from unbound nitrogen to the bound carboxylate oxygen atoms.
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Affiliation(s)
- Rama Mohana Rao Dumpala
- Radioanalytical Chemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085, India
| | - Neetika Rawat
- Radioanalytical Chemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085, India.
| | - B S Tomar
- Radioanalytical Chemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085, India
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36
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Chatterjee S, Bryan SA, Casella AJ, Peterson JM, Levitskaia TG. Mechanisms of neptunium redox reactions in nitric acid solutions. Inorg Chem Front 2017. [DOI: 10.1039/c6qi00550k] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work explores the mechanisms of inter-conversions among the various oxidation states of neptunium in aqueous HNO3, and the effect of HNO3 on their electronic structures.
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Affiliation(s)
- Sayandev Chatterjee
- Energy and Environment Directorate
- Pacific Northwest National Laboratory
- Richland
- USA
| | - Samuel A. Bryan
- Energy and Environment Directorate
- Pacific Northwest National Laboratory
- Richland
- USA
| | - Amanda J. Casella
- Energy and Environment Directorate
- Pacific Northwest National Laboratory
- Richland
- USA
| | - James M. Peterson
- Energy and Environment Directorate
- Pacific Northwest National Laboratory
- Richland
- USA
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37
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Chatelain L, Tuna F, Pécaut J, Mazzanti M. Synthesis and SMM behaviour of trinuclear versus dinuclear 3d–5f uranyl(v)–cobalt(ii) cation–cation complexes. Dalton Trans 2017; 46:5498-5502. [DOI: 10.1039/c6dt04558h] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Trinuclear versus dinuclear heterodimetallic UVO2+⋯Co2+ complexes were selectively assembled via a cation–cation interaction by tuning the ligand. The trimeric complex, exhibits magnetic exchange and slow relaxation providing the first example of a U–Co exchange-coupled SMM.
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Affiliation(s)
- Lucile Chatelain
- Institut des Sciences et Ingénierie Chimiques
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
| | - Floriana Tuna
- School of Chemistry and Photon Science Institute
- The University of Manchester
- Manchester
- UK
| | | | - Marinella Mazzanti
- Institut des Sciences et Ingénierie Chimiques
- Ecole Polytechnique Fédérale de Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
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38
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Jin GB. Three-Dimensional Network of Cation-Cation-Bound Neptunyl(V) Squares: Synthesis and in Situ Raman Spectroscopy Studies. Inorg Chem 2016; 55:2612-9. [PMID: 26885939 DOI: 10.1021/acs.inorgchem.5b02955] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cation-cation interactions (CCIs) are an essential feature of actinyl chemistry, particularly neptunyl(V). To better understand the formation mechanisms of CCIs, the crystallization process of Np(V) CCI compounds has been explored during the evaporation of acidic Np(V) stock solutions using X-ray diffraction and both ex situ and in situ Raman spectroscopy. At least four Np solid products have been isolated from evaporation of the same Np(V) acidic solution. In situ evaporation using a continuous wave laser (532 nm) as a local heat source produced similar solid products to ex situ experiments with matching Raman signatures. The formation of these products is highly dependent on the evaporation conditions. Slower evaporation appears to favor the formation of a new neptunyl(V) compound, (NpO2)Cl(H2O)2 (1), over other solid products. The structure of 1 features a three-dimensional network of NpO2(+) cations, where neighboring Np(V) ions are only connected to each other through CCIs in a square arrangement. The O═Np═O stretching region shows similar Raman bands in both the solids and solution suggesting that CCIs between Np(V) cations exist prior to crystallization. These results provide new insight into the formation mechanism of Np(V) CCI compounds from solutions.
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Affiliation(s)
- Geng Bang Jin
- Chemical Sciences and Engineering Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
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39
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Zheng XJ, Bell NL, Stevens CJ, Zhong YX, Schreckenbach G, Arnold PL, Love JB, Pan QJ. Relativistic DFT and experimental studies of mono- and bis-actinyl complexes of an expanded Schiff-base polypyrrole macrocycle. Dalton Trans 2016; 45:15910-15921. [DOI: 10.1039/c6dt01625a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Relativistic DFT calculations present accurate geometries of complexes and redox properties, confirmed by the newly-developed experimental syntheses.
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Affiliation(s)
- Xiu-Jun Zheng
- Key Laboratory of Functional Inorganic Material Chemistry of Education Ministry
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- China
| | - Nicola L. Bell
- EaStCHEM School of Chemistry
- University of Edinburgh
- Edinburgh
- UK
| | | | - Yu-Xi Zhong
- Key Laboratory of Functional Inorganic Material Chemistry of Education Ministry
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- China
| | | | - Polly L. Arnold
- EaStCHEM School of Chemistry
- University of Edinburgh
- Edinburgh
- UK
| | - Jason B. Love
- EaStCHEM School of Chemistry
- University of Edinburgh
- Edinburgh
- UK
| | - Qing-Jiang Pan
- Key Laboratory of Functional Inorganic Material Chemistry of Education Ministry
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- China
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40
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Tecmer P, Hong SW, Boguslawski K. Dissecting the cation–cation interaction between two uranyl units. Phys Chem Chem Phys 2016; 18:18305-11. [DOI: 10.1039/c6cp03542f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A theoretical study of the CCIs between two bare uranyl units and their spectroscopic characterization.
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Affiliation(s)
- Paweł Tecmer
- Institute of Physics
- Faculty of Physics
- Astronomy and Informatics
- Nicolaus Copernicus University in Torun
- 87-100 Torun
| | - Sung W. Hong
- Melbourne Dental School
- University of Melbourne
- Parkville
- Australia
| | - Katharina Boguslawski
- Institute of Physics
- Faculty of Physics
- Astronomy and Informatics
- Nicolaus Copernicus University in Torun
- 87-100 Torun
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41
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Clark AE, Samuels A, Wisuri K, Landstrom S, Saul T. Sensitivity of Solvation Environment to Oxidation State and Position in the Early Actinide Period. Inorg Chem 2015; 54:6216-25. [DOI: 10.1021/acs.inorgchem.5b00365] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Aurora E. Clark
- Department of Chemistry and the Materials
Science and Engineering Program, Washington State University, Pullman, Washington 99164, United States
| | - Alex Samuels
- Department of Chemistry and the Materials
Science and Engineering Program, Washington State University, Pullman, Washington 99164, United States
| | - Katy Wisuri
- Department of Chemistry and the Materials
Science and Engineering Program, Washington State University, Pullman, Washington 99164, United States
| | - Sarah Landstrom
- Department of Physics, Kutztown University, Kutztown, Pennsylvania 19530, United States
| | - Tessa Saul
- Moscow High School, Moscow, Idaho 83843, United States
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42
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Zegke M, Nichol GS, Arnold PL, Love JB. Catalytic one-electron reduction of uranyl(VI) to Group 1 uranyl(V) complexes via Al(III) coordination. Chem Commun (Camb) 2015; 51:5876-9. [PMID: 25727815 DOI: 10.1039/c5cc00867k] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Reactions between the uranyl(VI) Pacman complex [(UO2)(py)(H2L)] of the Schiff-base polypyrrolic macrocycle L and Tebbe's reagent or DIBAL result in the first selective reductive functionalisation of the uranyl oxo by Al to form [(py)(R2AlOUO)(py)(H2L)] (R = Me or (i)Bu). The clean displacement of the oxo-coordinated Al(III) by Group 1 cations has enabled the development of a one-pot, DIBAL-catalysed reduction of the U(VI) uranyl complexes to a series of new, mono-oxo alkali-metal-functionalised uranyl(V) complexes [(py)3(MOUO)(py)(H2L)] (M = Li, Na, K).
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Affiliation(s)
- Markus Zegke
- EaStCHEM School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh EH9 3FJ, UK.
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43
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Yusov AB, Grigor’ev MS, Fedoseev AM, Moisy P, Shilov VP, Gogolev AV. Behavior of Np(V), Pu(V), and Am(V) in solutions of pyridine-2,6-dicarboxylic (dipicolinic) acid and synthesis of crystalline compounds. RADIOCHEMISTRY 2015. [DOI: 10.1134/s1066362215010026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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44
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Natrajan LS, Swinburne AN, Andrews MB, Randall S, Heath SL. Redox and environmentally relevant aspects of actinide(IV) coordination chemistry. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2013.12.021] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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45
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Computational Redox Potential Predictions: Applications to Inorganic and Organic Aqueous Complexes, and Complexes Adsorbed to Mineral Surfaces. MINERALS 2014. [DOI: 10.3390/min4020345] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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46
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Cation‐Mediated Conversion of the State of Charge in Uranium Arene Inverted‐Sandwich Complexes. Chemistry 2013; 19:17528-40. [DOI: 10.1002/chem.201302752] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Indexed: 11/07/2022]
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47
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Mkandawire M. Biogeochemical behaviour and bioremediation of uranium in waters of abandoned mines. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:7740-7767. [PMID: 23354614 DOI: 10.1007/s11356-013-1486-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Accepted: 01/09/2013] [Indexed: 06/01/2023]
Abstract
The discharges of uranium and associated radionuclides as well as heavy metals and metalloids from waste and tailing dumps in abandoned uranium mining and processing sites pose contamination risks to surface and groundwater. Although many more are being planned for nuclear energy purposes, most of the abandoned uranium mines are a legacy of uranium production that fuelled arms race during the cold war of the last century. Since the end of cold war, there have been efforts to rehabilitate the mining sites, initially, using classical remediation techniques based on high chemical and civil engineering. Recently, bioremediation technology has been sought as alternatives to the classical approach due to reasons, which include: (a) high demand of sites requiring remediation; (b) the economic implication of running and maintaining the facilities due to high energy and work force demand; and (c) the pattern and characteristics of contaminant discharges in most of the former uranium mining and processing sites prevents the use of classical methods. This review discusses risks of uranium contamination from abandoned uranium mines from the biogeochemical point of view and the potential and limitation of uranium bioremediation technique as alternative to classical approach in abandoned uranium mining and processing sites.
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Affiliation(s)
- Martin Mkandawire
- Verschuren Centre for Sustainability in Energy and the Environment, Cape Breton University, P.O. Box 5300, 1250 Grand Lake Road, Sydney, Nova Scotia, Canada, B1P 6L2,
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48
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Jin GB. Mixed-Valent Neptunium(IV/V) Compound with Cation–Cation-Bound Six-Membered Neptunyl Rings. Inorg Chem 2013; 52:12317-9. [DOI: 10.1021/ic4021492] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Geng Bang Jin
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
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49
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Camp C, Pécaut J, Mazzanti M. Tuning Uranium–Nitrogen Multiple Bond Formation with Ancillary Siloxide Ligands. J Am Chem Soc 2013; 135:12101-11. [DOI: 10.1021/ja405815b] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Clément Camp
- Laboratoire de Reconnaissance
Ionique et Chimie de
Coordination, SCIB, UMR-E3 CEA-UJF, INAC, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 09
| | - Jacques Pécaut
- Laboratoire de Reconnaissance
Ionique et Chimie de
Coordination, SCIB, UMR-E3 CEA-UJF, INAC, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 09
| | - Marinella Mazzanti
- Laboratoire de Reconnaissance
Ionique et Chimie de
Coordination, SCIB, UMR-E3 CEA-UJF, INAC, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 09
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Tecmer P, Govind N, Kowalski K, de Jong WA, Visscher L. Reliable modeling of the electronic spectra of realistic uranium complexes. J Chem Phys 2013; 139:034301. [DOI: 10.1063/1.4812360] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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